Androgens play an essential role in the differentiation, development and maintenance of epididymal function. The long term objective of this laboratory is to define the mechanisms by which androgens regulate these processes. Toward this goal, acidic epididymal glycoprotein (AEG), an androgen-regulated secretory protein of the rat epididymis, has been chosen as a model to examine the regulation of gene expression in the epididymis. Preliminary studies have indicated that androgen is necessary but not sufficient to activate AEG gene transcription during postnatal development. The objective of this proposal is to continue to explore the regulation of AEG gene expression by identifying factors which act in concert with androgen to stimulate AEG synthesis. The first of five specific aims which have been proposed to accomplish this objective is to examine the effect of pituitary hormones on AEG expression. AEG mRNA levels will be measured in hypophysectomized animals and compared to intact control animals and hypophysectomize animals receiving hormone replacement. The second aim of this proposal is to examine the effect of pituitary hormones on AEG expression. AEG mRNA levels will be measured in hypophysectomized animals and compared to intact control animals and hypophysectomized animals receiving hormone replacement. The second aim of this proposal is to determine the role of perinatal androgens in regulating AEG synthesis. The hypothesis that perinatal androgens stimulate the synthesis of androgen- regulated proteins required for AEG synthesis will be tested by examining the expression AEG in the epididymis of female animals virilized in utero. The third specific aim is to test the hypothesis that the activation of AEG gene transcription during epididymal development occurs simultaneously with nucleotide probes will localize androgen receptor mRNA within specific cell types during development. The fourth specific aim is to isolate and characterize the gene for AEG. This will lead to the identification of important regulatory sequences and provide the template needed to perform the experiments outlined in the fifth specific aim. The fifth aim is to identify proteins which bind to the AEG gene. The 5' flanking region of the AEG gene will be used in DNase I footprinting assays to identify nucleotide sequences involved in the binding of trans-acting elements. Epididymis-specific DNA-binding proteins will be identified by comparing the DNase I footprinting patterns generated by nuclear extracts prepared from epididymis and non-AEG synthesizing tissues. This research will further the understanding of male reproductive tract differentiation and provide insight into the etiology of ambiguous genitalia and male infertility.